Explanation: 2, 4-dinitrophenol (DNP), as a uncoupling agents, are lipid soluble small molecules that can bind H+ ions and transport across membrane. It prevents the formation of proton gradient therefore no ATP can be made by oxidative phosphorylation.

3. When you created a fusion between the trp Operon, which encodes the enzymes for tryptophan biosynthesis, under the regulatory control of lac promoter. Under which of the following conditions will tryptophan synthase be induced in the strain that carries the chimeric operator fused operons?

1. Only when both lactose and glucose are absent

2. Only when both lactose and glucose are present

3. Only when lactose is absent and glucose is present

4. Only when lactose is present and glucose is absent

Ans: 4. Only when lactose is present and glucose is absent

Explanation: Lac repressor protein always binds to the operator there by blocking transcription.

In the presence of glucose and lactose, the bacterium will utilize glucose as the primary Carbon source-----à transcription off Lac Operon off

In the presence of lactose alone, Lactose binds to the lac repressor--àtranscription on.

4.Which of the following atomic nuclei cannot be probed by nuclear magnetic resonance spectroscopy?

1. 1H

2. 31P

3. 18O

4. 15N

Ans:3. 18O

Explanation:

1H: most commonly used

15N, 31P: used in biochemical studies

18O: not used

5. In the case of monoclonal antibody production by Hybridoma technology, myeloma cells used lack the enzyme hypoxanthine-guanine phosporibosyl transferase (HGPRT) such that fused cells can only survive when selected on Hypoxanthine-aminopterin-thymidine (HAT). What is the role of Aminopterin in this medium?

7. The cap binding protein (eIF4E), which is involved in global regulation of translation is highly regulated in eukaryotic cells. In an experiment, a researcher transfected mammalian cells with (eIF4E) gene for its over expression. Due to this the cell will undergo

8.Bacteriophage T4 infects E.coli and injects its DNA inside the cell. The transcription of viral genes occurs in three stages: immediate early, early and late. All the promoters on viral genome are available, but the control takes place at the level of

9. Which of the following genes was engineered in the ‘Flavr Savr’ transgenic tomato variety?

1. 1-amino cyclopropane 1- carboxylic acid synthase

2. 1-amino cyclopropane 1- carboxylic acid oxidase

3.Expansin

4.Polygalactouronase

Ans: 4.Polygalactouronase

‘Flavr Savr’ tomato: has increased shelf life by silencing the polygalactouronase gene involved in ripening by anti sense technology.

10. A plot of soil contaminated with diesel oil was inoculated with oyster mushrooms. After 4 weeks, more than 95% of the polycyclic aromatic hydrocarbons had been reduced to non-toxic compounds. The process is called

1. phytoremediation

2. chemoremediation

3. mycoremediation

4. zoo remediation

Ans: 3. mycoremediation

Explanation: Bioremediation is the process of cleaning up or degrading environmental contaminants using biological organisms especially microbes.

Question Source: In an experiment conducted in conjunction with Dr. S. A. Thomas, a major contributor in the bioremediation industry, a plot of soil contaminated with diesel was inoculated with mycelia of oyster mushrooms; traditional bioremediation techniques (bacteria) were used on control plots. After four weeks, more than 95% of many of the PAH (polycyclic aromatic hydrocarbons) had been reduced to non-toxic components in the mycelial-inoculated plots. It appears that the natural microbial community participates with the fungi to break down contaminants, eventually into carbon dioxide and water. Wood-decay fungi are particularly effective in breaking down aromatic pollutants (toxic components of petroleum), as well as chlorinated compounds (certain persistent pesticides; Battelle, 2000).

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comments:

I would like to get the answer along with exaplanation of a part c question which was on apoptosis. In the question it was given that in one cell line Cyt C is microinjected and in other cyt c is microinjected but at the same time Bak and Bax are removed.

Easy. The external and internal apoptotic pathways are connected. So, in the first case, the Cytochrome C is directly injected and so the external pathway is omitted and apoptosis occurs. In the second case, even though the Bak and Bax systems are inactivated, it doesn't matter, as the cytochrome C is directly injected. So in both cells, the apoptotic output is the same. Answer is the graph with same levels of apoptosis.